Safety welding tongs



Sept. 8, 1925.

ENQ

a, Ulo'vwm am M R. w. ERICKSON E'r Al.

SAFETY wELDrNG Tones Filed Aug. 9. 1924 *Q N m @l Sept. 8, 1925.

R. w. ERICKSON ET Al. SAFETY WELDING ToNGsy Filed Aug. 9. 1924 351gSuma;

2 sneetssneet 2` Patented Sept. `8, 1.925.

UNITED STATES PATENT OFFICE.

noBEar wu. EaIcxsoN, or JERSEY crrY, NEW JERSEY, AND Ircam J. ocoNNELL,

or nnooxmm, NEW vonk.

sun'ry WELDING Tones.

Application filed August D, 1924. Serial No. 781,200.

To all whom it may concern:

Be it known that we, ROBERT W. En1ox` soN and MICHAEL J. yOCONNELL,citizens' of the United States, and residents of Jerseyl City, NewJersey, and Brooklyn, New York, respectively, have invented certain newand useful Improvements in Safety Welding Tongs, of which the followingis a speci.- fication.

The invention relates to improvements in a tool-for holding an electrodeor wire pencil such as is used in arc welding.

In this type of welding an electric current is used to cause therequired' heating which in practice is eiected by. drawing an arcbetween the work to be welded and the electrode. To do this it isnecessary to connect a wire Vcarrying the current to the object.

to be welded andanother wire of opposite electrical polarity totheelectrode, which completes the circuit when the electrode makes contactwith the work to be welded. Under such conditions, the electrode and theun-insulatedcparts of its holder must be carefully handle particularlyso when laying it aside for purposeA of inspecting the` work, and soforth. i Also when so laid aside it must b'e insulated from theobjectwhich is being welded, otherwise a short-circuit will be formed.This is very often troublesome to accomplish, for instance,=whenwelding-on large objects such as steel ships, locomotives, and so forthand on objects in electrical contact with the earth.

The most common methodV of insulating the usual form ofv holder when solaid aside consists of laying it on a wood board or hanging it over awood scaffold or the like. As potentials up to 500 volts are often .usedit can be readily seen that the live electrode when so laid asideconstitutes -a hai'ai'd to the operator and other workmen in thevicinity who may accidentally come into contact with it. y

Our improved type of welding tongs overcomes thls hazard as the current1s auto-` .matically cut olf from the electrode and exposed live partswhen the o erator releases the hand grip, and it may t erefore be laidaside without insulating it from the work.

This is a great advantage from 'a standpoint of safety, and also resultsin greater eiciency since the operator and workmen in vicinity are thusable to devote their undivided attention to the work in hand.

These and other advantages will be apparent from the followingspecification when read in connection with the accompanying drawings inwhich- Fig. 1 is a longitudinal section illustrating one embodiment ofthe invention;

Fig. 2 is a horizontal to plan;

Fig. 3 is an end view om the right of Fig. 2; l v

Fig. 4 is a detail section on line 4-'4 of .Fig 1;

Fig. 5 is aview of a modified construction; f

Fig. 6 is aside view showing an alternative structure. v

Referring to the drawings, the main body 10 of the tool is screwthreadedat 12 ,for adjustably securing thereto an extension tip 14whichcan be locked in its adjusted position byl tightening the screw 16 whichpasses vthrough 1n the end o the body 10;

' `In the end of the t1 14 is a fixed jaw 20 which is rovided wit athreaded shank 22 passing t Arough a clearance hole 24 in the end ofl hetip. Insulating washers 26 and `'ns twoupstanding lugs on oposite sidesof-a longitudinal kerf 18 formed 28 are provided on opposite sides ofthe end wall of the tip so as to prevent thepassage `(lurrent from thejaw to the tip andI mam Y cure the jaw to the tip so thatlit canbereplaced when badlylworn -or burnt. The jaw 2Q is formed with a centrallongitudinal cavity 32 and a 'transverse aperture 34 through which thewelding electrode or wire pencil 36 passes. apertures 38 of greaterdiameter than the electrodes so that current therefrom will not passtothe tip. i

The movable jaw ,of the tongs comprises a renewable contact 'tip 40which'is threaded on the end 42 of a longitudinallyl extending shank 44,a 'jamb nut adjustably secure the co/ntact tipvor )aw to said shank. 'Aninsulating washer 48 encircles the shank 44 and engiages a shoulder 50formed in the main bo of the tongs which serves as a back stop or themovable The tip `14 is provided with and a nut 30 serves to removablyse-l 46 beingv provided to rounded for the greater part of its length byan insulating sleeve 52 which is secured thereto by a pin or rivet 54.This sleeve slides freely in a rearward hub extension or guide 56 formedin the main body l0.

Located to the rear of the hub 56 and secured to the sleeve is a splitcollar 58 and between the latter and the hub is a compression spring 60which tends to normally hold the movable jaw 40 away from the fixed jaw20 or in substantially the position shown in Fig. 1.

For moving the jaw 40 forward to forcibly clamp the electrode 36 to thefixed jaw 20, hand grips 62 are provided which are pivoted at 644 tolugs on the mai-n body l() and at 66 to toggle links 68 which are inturn pivoted to the collar 58 carried -by the above mentioned sleeve 52.

To the rear end of the shank 44 a flexible conductor 72 is connected bymeans of a metal sleeve 74 and suitable binding screws 76 and 78 asshown.

In Fig. 6 we have shown a slight modification wherein the movable jaw isactuated by a single toggle and hand grip; in this form the body isJformed with a. guide extension 80 on which the collar 58 slides and theouter surface 82 serves as a fixed hand grip.

Fig. 6 shows an alternative construction in which the tip 14a is formedof insulation screwed into the body 10, and has riveted thereto a fixedjaw 20a which is chambered to slidingly support a moving j aw 40il whosemovement is limited by a pin and slot connection 15-17. The jaw 40a isforced forward vby a headed shank 44a hich is actuated inthe same manneras the shank 40 above described.' u

In operation a wire pencil or electrode 36 is inserted-through theopening, in the tip of the tongs and the hand grips are pressed togetherwhich action results in moving the jaw 40 into electrical contact withthe electrode and also forcibly clamping thc-latter between the twojaws. The toggle action of the hand grips permits the exertion of atremendous force inasmuch as the ratio of the pressure exerted on thehand grips to the pressure of the movable jaw on the electrode increasesas the tangent of the angle included between a line passing through thepivots of the links 68 and a plane perpendicular to the axis of theshank 44. e

When the operator completes welding a piece of work the circuit to theelectrode is automatically broken by releasing the pressure on the handgrips and the tongs can be laid aside without danger of causin shortcircuits or injuring persons in its vicinity.

The desi is such that the electrode is located su ciently remote fromthe hand grips so that the heat dueto contact resistance or heat ofconduction will be dissipated before reaching the hand grips.

' the latter toward grip on the welding electrode, a spring tend- Theparts which are subject to wear or burning can be readily replaced orcan be adjusted to compensate for such wear.

Though we' have described with great particularity specific embodimentsof the invention illustrated, it is not to be construed that `we -arelimited thereto as various moditications and substitutions ofequivalents may be made without departing from the invention as definedin the appended claims.

lVhat we claim is:

l. A welding tongs including coacting members arranged to jointly engagethe welding electrode, means for forcing one of said members toward theother to exert a grip on the electrode, a spring tending to hold saidmembers apart and insulating means between said members.

2. A welding tongs including coacting members adapted to jointly clampand completev the welding circuit through a welding electrode, means forinsulating said members from one another, a hand grip for forcing one ofsaid members toward the other, and means for separating said members andbreaking the welding circuit when said hand grip is released.

3. A welding tongs comprising a main body having a lixed jaw secured tobut insulated therefrom, a movable jaw insulated from said body, means.tending to normally hold'said jaws apart and toggle mechanism forforcing 'the movable jaw toward the fixed jaw. k

4. A welding tongs comprising a main body having a fixed jaw adjustablysecured thereto, a movable jaw connected with an electric conductor,hand grip for moving tlie fixed jaw to exert a ing to 'normally holdsaid jaws apart and means for insulating said movable jaw from both thehand grip and the main body.

5. A welding tongs comprising a main body having fixed and movable jawsbetween which a welding electrode is adapted to be clamped, means forsupplying current to the movable jaw, manually o erated means for movingthe latter jaw an adjustable means for compensating for wear on saidjaws.

b A welding tongs comprising a main o ya a jaw detachably secured in thelatter, a movable jaw having an elongated shank carrying an insulatingsleeve guided in said body, a hand grip pivoted at o'ne end to saidbody, a toggle link secured to said sleeve and connected to said handgrip, a spring tending to hold said jaws apart and a conductor connectedto said slink.

an adjustable member carried thereby,

In testimony whereof, we have hereunto signed our names.

